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Education Bookcast

May 7, 2023

In the second part of this two-part episode about lessons learned from my time working in the education technology sector, I wanted to share a very significant quantitative finding to improve learning: what I call the "90% rule".

Desirable difficulties is a concept that many know about and try to apply to teaching situations, but there is a question of how difficult one should make things. Surely there is a level at which things are too difficult? In which case, what is the perfect level of difficulty that we should aim for? The secret is this 90% number.

Enjoy the episode.



Eglington, L.G., Pavlik Jr, P.I. Optimizing practice scheduling requires quantitative tracking of individual item performance. npj Sci. Learn. 5, 15 (2020).

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